The present invention relates generally to biosynthetic processes, and more specifically to organisms having 1,4-butanediol and gamma-butyrolactone biosynthetic capability.
1,4-Butanediol (14-BDO) is a polymer intermediate and industrial solvent with a global market of about 3 billion lb/year. 14-BDO is currently produced from petrochemical precursors, primarily acetylene, maleic anhydride, and propylene oxide. For example, acetylene is reacted with 2 molecules of formaldehyde in the Reppe synthesis reaction (Kroschwitz and Grant, Encyclopedia of Chem. Tech., John Wiley and Sons, Inc., New York (1999)), followed by catalytic hydrogenation to form 1,4-butanediol. Downstream, 14-BDO can be further transformed; for example, by oxidation to gamma-butyrolactone (GBL) or hydrogenolysis to tetrahydrofuran (THF). These compounds have varied uses as polymer intermediates, solvents, and additives, and have a combined market of nearly 2 billion lb/year.
Gamma-butyrolactone (GBL) is a chemical intermediate and common solvent with a global market of about 0.5 billion lb/year. GBL has wide applications. GBL serves as a chemical intermediate in the manufacture of pyrrolidones that are widely used in the pharmaceutical industry. It can be used in the production of pesticides, herbicides and plant growth regulators. GBL is also used as an aroma compound, as a stain remover, as a superglue remover, as a paint stripper, and as a solvent in some wet aluminum electrolytic capacitors. Currently, GBL is mainly synthesized through 14-BDO from crude oil and/or natural gas derived feedstocks by the Reppe acetylene chemistry.
Microbial organisms and methods for effectively co-producing commercial quantities of 14-BDO and GBL are described herein and include related advantages.